THE World Heritage Committee has been told that $1.2 billion being spent on water quality initiatives on the Great Barrier Reef will be wasted if more than 97 million tonnes of dredge spoil is dumped in the World Heritage Area.
A letter from respected water quality scientist James Cook University's Professor Jon Brodie was given to the committee meeting in Doha on Tuesday night Australian time.
The meeting was the latest to consider putting the reef on the World Heritage "in danger" list, due to continued declines in the overall reef's health and a raft of developments proposed and underway.
It also comes after the Abbott government applied to de-list previously World Heritage-listed forests in Tasmania, and follows the House of Representatives passing new laws handing federal environmental assessments to states on Monday.
In the letter, Prof Brodie compared the gains made in reducing sediment run-off into the reef catchment from 2009 to 2014, of 123,000 tonnes a year; with the proposed rate of dredge spoil dumping in the World Heritage Area at a "potential rate of 10 million tonnes per year.
The comparison, based on the reef strategic assessment and reports on the largely successful Reef Plan, shows how the progress made with landholders in Queensland could be un-done by the proposed dredging projects.
Those figures also undermine arguments that the proposed dredging is a minor issue and the proposed dredge spoil dumping rates are actually greater than that reduced under the Reef Plan.
Among the projects were developments underway or proposed at the five major reef ports - Gladstone, Abbot Point, Hay Point, Cairns and Townsville - totalling 97 million tonnes at a rate of about 10 million tonnes generated each year for up to a decade.
"It can easily be seen that the proposed amount of sediment to be dredged and potentially dumped (10 million tonnes per year), is large (eight times as much) in comparison to the gains we are making in reducing sediment loading of the World Heritage Area through Reef Plan of about 120,000 tonnes per year," Prof Brodie wrote.
"In fact if this amount of spoil dumping occurs it will wipe out all the gains made, and likely to be made, over the period 2009 - 2018 under Reef Plan."
Prof Brodie wrote the spending on the Reef Plan - about $600 million between 2009 and 2013 and a similar amount between 2014 and 2014 would also be undermined if the proposed port developments went ahead.
"So in total $1200 million will be spent in reducing pollutant loading of the reef World Heritage Area from 2009 - 2018," he wrote.
"That this expenditure could be, in essence, wasted along with the decades long work of thousands of people responsible for our successes under Reef Plan is tragic."
The letter follows the Queensland Government and Federal Government touting the progress made on addressing the committee's concerns, claims defended by the resources industry but questioned by the scientific community and environmental groups.
A decision by the committee was expected this week on whether it would put the reef on the "in danger" listing, which could be deferred until next June, with expectations for more action in Australia.
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